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We have an update on what the State Department has described as a health attack on U.S. government officials in Cuba. The U.S. now says at least 16 Americans became ill with symptoms including hearing loss. But the cause still hasn't been confirmed. NPR's Michele Kelemen reports.
MICHELE KELEMEN, BYLINE: The problems began late last year when some Americans living in diplomatic housing in Havana suffered headaches and hearing loss. CBS News is reporting that some even had minor traumatic brain injuries. While State Department spokesperson Heather Nauert wouldn't confirm that, she did say at least 16 Americans were affected.
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HEATHER NAUERT: They have been provided medical treatment in the United States as well as in Cuba. We take the situation extremely seriously. We are trying to provide them the help, the medical care, the treatment and the support that they need and the support that they deserve.
KELEMEN: The U.S. expelled two Cuban diplomats in May in protest. A former Bush administration official, Jose Cardenas, says the U.S. should do more.
JOSE CARDENAS: We are talking about really an egregious violation of international treaties and norms on the treatment of diplomats in foreign countries. And this is unprecedented.
KELEMEN: Cuba has a long history of harassing U.S. diplomats, he says. But this appears to be something new and came at a time when the Obama administration had eased up on travel and trade restrictions.
CARDENAS: It certainly is more sinister in that U.S. diplomats were apparently unaware that it was happening to them.
KELEMEN: Diplomats who ran the U.S. mission in the past certainly knew they were being watched. Vicki Huddleston served in Havana from 1999 to 2002.
VICKI HUDDLESTON: From my fifth-floor office which was all glass on three sides, I could look right across the street and see cameras and listening devices pointed at me. In fact in the residences, there were so many listening and video devices that our security people didn't even bother to look for them because they would just be replaced.
KELEMEN: Huddleston, who's writing a memoir about her time in Cuba, says one of her colleagues came home to find his cat dead and suspected the Cuban authorities were responsible. She says the Cubans have easy access to diplomatic housing.
HUDDLESTON: All the missions rent their houses from the Cuban government. And all the staff in the houses - say you have a maid or you have a gardener that you employ - all of them through the Cuban government. The government provides all our staff. And many are very, very loyal. But everybody has to report.
KELEMEN: When John Caulfield took over the U.S. diplomatic mission in Havana in 2011, harassment was on the rise.
JOHN CAULFIELD: There were more in-your-face kind of activities by the intelligence services, things like going into your homes and emptying your water tanks, turning off your electricity, rearranging things inside your house, your clothing - these reminders that we are here; we are looking at you - and a way to - you know, would get at your morale.
KELEMEN: That sort of tapered off by the end of his tour in 2014, he says, but the surveillance continued. And he suspects that Cuba may have been using faulty equipment, which caused hearing loss and headaches among Americans stationed there last year.
CAULFIELD: There's no way the Cubans, if they did this, would ever admit it. I mean just forget that. The most we can hope for is they stop doing it and don't do it again.
KELEMEN: The State Department says the incidents have stopped. Cuba's foreign ministry says it took the issue with, quote, "the utmost seriousness." Michele Kelemen, NPR News, Washington. Transcript provided by NPR, Copyright NPR.